H.R. 4345 — To amend title XVIII of the Social Security Act to expand the definition of critical access hospital under the Medicare program to include certain hospitals on Indian reservations.

This section expands Medicare critical access hospital (CAH) designation criteria (i.e., small rural facilities eligible for cost-based reimbursement to ensure healthcare access) to exempt certain facilities on Indian reservations from distance and bed limits. (1) It makes the 35-mile proximity requirement and total bed cap of 25 (with limited exceptions) subject to a new subparagraph (F); and (2) effective August 1, 2025, it authorizes states to designate a facility on a reservation (as defined in section 4 of the Indian Health Care Improvement Act) as a CAH without regard to distance to other hospitals or facilities. Such facilities may also establish unlimited psychiatric and rehabilitation distinct part units without regard to the bed limit, and the Secretary may not count those beds when determining if the facility primarily provides inpatient hospital services.